1. Field of the Invention
The present invention relates an infrared receiver chip for installation in a standardized lead frame of an infrared receiver module.
2. Description of the Background Art
Infrared receivers are used for data connections in carrier frequency modulated transmission applications, for example. Infrared receivers are especially known for electronic entertainment devices such as televisions, DVD players, satellite receivers, video recorders, CD players, and the like. In these applications, a remote control, for example, transmits IR light signals toward the infrared receiver module, where the received light signals are converted to electrical signals.
In general, various designs of infrared module exist, with at least two different designs of infrared receiver chips being used in order to accommodate the installation requirements of the different lead frame designs in the individual infrared receiver modules. In general, three standardized lead frame designs exist, which are explained in detail below with reference to FIGS. 5 through 7.
FIG. 5 illustrates a top view of a conventional infrared receiver chip 1 mounted in a first standardized lead frame 2. As can be seen in FIG. 5, the infrared receiver chip 1 has, for appropriate installation in the first standardized lead frame 2, at least one signal input contact area 5, a ground contact area 6, a signal output contact area 7, and a power supply contact area 8. The signal input contact area 5 is used to connect to a signal input point IN on the lead frame side, the ground contact area 6 is used to connect to a ground point GND on the lead frame side, the signal output contact area 7 is used to connect to a signal output point OUT on the lead frame side, and the power supply contact area 8 is used to connect to a power supply point VCC on the lead frame side. The individual connections and contact areas are connected by bond wires 9.
In addition, the infrared receiver chip 1 has additional contact areas 10 for welding the infrared receiver chip 1 into the associated lead frame 2.
FIGS. 6 and 7 illustrate a top view of a conventional infrared receiver chip 1 mounted in a second standardized lead frame 3 or in a third standardized lead frame 4. The infrared receiver chips 1, in turn, have the above-described contact areas 5, 6, 7, 8, and 10 for connection to the associated lead-frame-side signal input point, ground point, signal output point, and power supply point.
In this regard, the three standardized lead frames 2, 3, and 4 differ in that the individual connection points IN, GND, OUT, and VCC are provided at different positions, as can be seen in FIGS. 5, 6, and 7.
The second standardized lead frame 3 in FIG. 6 differs from the first standardized lead frame 2 in FIG. 5 in that the power supply point VCC is arranged on the opposite side of the signal output point OUT with respect to the infrared receiver chip 1 used, instead of being positioned on the same side.
The third standardized lead frame 4 in FIG. 7 differs from the first standardized lead frame 2 in FIG. 5 in that the signal output point OUT is arranged opposite the ground point GND with respect to the infrared receiver chip 1 used, and is positioned between the signal input point IN and the power supply point VCC. In addition, the power supply point is arranged on a different side edge of the chip 1 in comparison to the second standardized lead frame 3 in FIG. 6.
A basic problem in connecting such connection points with the contact areas provided on the infrared receiver chip 1 is that the bond wires 9 have to run as directly as possible from the given connection point to the associated contact area in order to keep the length of the bond wires as short as possible so that electromagnetic interference effects can be minimized. Furthermore, in order to avoid a short circuit of these lines, the individual bond wires 9 of the individual connections cannot cross or intersect.
In order to fulfill these requirements for installation in the different designs of standardized lead frames 2, 3, 4, at present there exist multiple different designs of infrared receiver chips 1 with different geometric arrangements of the individual contact areas.
For installation of an infrared receiver chip 1 in the first standardized lead frame 2 from FIG. 5 and the second standardized lead frame 3 from FIG. 6, a uniform infrared receiver chip 1 can be used, which, merely by rotation, permits a suitable orientation of the individual contact areas with respect to the associated contact points.
For installation of an infrared receiver chip 1 in the third standardized lead frame 4 from FIG. 7, however, such a receiver chip does not fulfill the requirements described above, so a different design of infrared receiver chip 1 is necessary in which the individual contact areas have a different geometric arrangement, as can be seen in FIG. 7.
However, this approach has been found to have the disadvantage that logistical management of two differently designed receiver chips, which under certain circumstances may also have different transmission protocols, is very resource-intensive and results in increased expenditure for logistics, and thus in a higher selling price.